/**
 * Created with IntelliJ IDEA.
 * Description:单链表
 * User: 晓星航
 * Date: 2022-10-29
 * Time: 15:27
 */
//ListNode代表一个节点
class ListNode {
    public int val;
    public ListNode next;//ListNode储存的是结点类型

    public ListNode (int val) {
        this.val = val;
    }

}
public class MyLinkedList {
    public ListNode head;//链表的头引用

    public void creatList() {
        ListNode listNode1 = new ListNode(12);
        ListNode listNode2 = new ListNode(23);
        ListNode listNode3 = new ListNode(34);
        ListNode listNode4 = new ListNode(45);
        ListNode listNode5 = new ListNode(56);
        listNode1.next = listNode2;
        listNode2.next = listNode3;
        listNode3.next = listNode4;
        listNode4.next = listNode5;
        this.head = listNode1;
    }
    //查找是否包含关键字key是否在单链表当中
    public boolean contains(int key) {
        ListNode cur = this.head;
        while (cur != null) {
            if (cur.val == key) {
                return true;
            }
            cur = cur.next;
        }
        return false;
    }
    //得到单链表的长度
    public int size(){
        int count = 0;
        ListNode cur = this.head;
        while (cur != null) {
            count++;
            cur = cur.next;
        }
        return count;
    }
    //头插法
    public void addFirst(int data) {
        ListNode node = new ListNode(data);
        node.next = this.head;
        this.head = node;
        /*if (this.head == null) {
            this.head = node;
        } else {
            node.next = this.head;
            this.head = node;
        }*/
    }
    //尾插法
    public void addLast(int data) {
        ListNode node = new ListNode(data);
        if (this.head == null) {
            this.head = node;
        } else {
            ListNode cur = this.head;
            while (cur.next == null) {
                cur = cur.next;
            }
            cur.next = node;
        }
    }
    //任意位置插入,第一个数据节点为0号下标
    public boolean addIndex(int index,int data) {
        return true;
    }
    //删除第一次出现关键字为key的节点
    public void remove(int key) {

    }
    //删除所有值为key的节点
    public void removeAllKey(int key) {

    }
    //打印链表中的所有元素
    public void display() {

    }
    //清除链表中所有元素
    public void clear() {

    }
}
